1909] 



OLSSON-SEFFER— VEGETATION ON SEA SHORES 



99 



in Table IV. 



middle beach at the same 

 Lees existing may be acco 



topography and by the fact that the upper beach here was covered 

 with a sparse vegetation consisting of various low herbs. 



On the littoral dune the temperature conditions are somewhat vary- 

 ing, usually higher on the landward slope, and a rise in temperature 

 can also be noticed with an increase in the height of the dune. The 



summit 



covered in large patches with vegetation, and the temperature differ- 

 ences between the open spots and those where plants occur are 

 considerable. 



Table VII shows a series of measurements made on the seaward 

 slope of the littoral dune at Fremantle, W. A., under conditions similar 

 to those given for previous observations from that locality. The 

 sand was fine white quartz. 



TABLE VII 



I 



2 



3 

 4 



5 



2 cm. 



5 cm. 



10 cm. 



35-2 



26.4 



23-5 



38.8 



27-3 



22 .6 



29.4 



20.5 



l8. I 



28.9 



21.3 



I9.4 



25.6 



18.7 



16.6 



temperature 



dune, 



a t a height of 6 m over the ocean level. The d 

 °f medium sand, somewhat yellowish in color. 



materi 



TABLE VIII 



2 cm. 



5 cm. 



10 cm. 



20 cm. 



24.2 

 23.0 

 18.2 



18.9 

 16.7 



21 .7 

 21 .2 

 16.8 



18.3 



i5-7 



50 cm 



19.8 

 18.9 



15-7 

 16.3 



14.0 



°n the landward slope, some 3 m from the top, the following meas- 



dements were obtained: 



